Up-country from Callander in Stirling Council area, there are a couple of restored railway viaducts which form important constituents of the National Cycle Network.
Back in 1961, I travelled by train from Oban to Glasgow by the rather roundabout route followed by the Callander and Oban Railway. The eastern section of the line (between Crianlarich and Callander) was due to be closed four years later, but events forced the closure a month early on 27 September 1965 when a landslide in Glen Ogle closed the line for good. After that date, the rail connection between Oban and central Scotland was by way of the West Highland Railway via Helensburgh.
Construction of the line back in 1866 to 1880 involved some formidable engineering challenges, including Glen Ogle and the Pass of Brander. In Glen Ogle, the railway climbs over a pass between Lochearnhead and Glen Dochart linking two tributaries of the Tay. Part way up the climb on the south side of the pass, the line crosses an a gash in the hillside, occupied by an apparently un-named stream which required the construction of a substantial viaduct. The viaduct stands to this day and has twelve stone arches with a concrete core, clad in local granite.
In recent years, the trackbed has been restored to a good surface and is followed by National Cycle Route 7 and by the Rob Roy Way, enabling cyclists and walkers to cross the pass whilst avoiding the busy A85 main road.
Only 4 Km further south, as Lochearnhead, National Cycle Route 7 crosses another noteworthy viaduct over Glen Kendrum. This viaduct is not on the same line as Glenogle, but the old Lochearnhead, St Fillans and Comrie branch railway which ran from Balquhidder Station on the main line along the north shore of Loch Earn. The Balquhidder to Comrie section was closed in 1951; the onward section from Comrie to Crieff in 1964.The cycle route drops steeply down the hillside at Lochearnhead to get from one old railway to another.
The old viaduct was demolished long ago, but a new bridge spanning the gap has been erected recently with funds raised to commemorate Nigel Hester, a young cyclist who was killed in 1997 "while cycling on the A9 near here". Could this be a mistake? The bridge enables cyclists to avoid the adjoining very busy A84; the nearest point of the A9 is 27 km away at Dunblane.